Dayton, Ohio, received top laurels from Healthgrades for having the lowest average risk-adjusted inhospital mortality rate across 16 conditions and procedures based on 2005-to-2011 data.

Healthgrades named the top 20 cities in its report, "America's Best Hospitals 2013: Navigating Variability in Hospital Quality" for conditions and procedures that included abdominal aortic aneurism repair, cardiac surgery, coronary intervention, stroke, heart attacks, heart failure and other vascular procedures, among others.

Despite the cities' overall low inhospital mortality rates, there was significant variation in rates among hospitals in each area, according to Healthgrades. For example, in its evaluation of heart attack treatments in No. 2-ranked Phoenix area, Healthgrades reported a range for risk-adjusted inhospital mortality rates of 1.68 percent to 10.37 percent.

“This means that some Phoenix area residents experienced a mortality rate up to six times higher than other residents did, depending on whether they were taken to the lowest-performing hospital versus the highest-performing hospital,” according to the report.

Cincinnati, which placed fourth, chalked up risk-adjusted in-hospital mortality rates of 1.3 percent to 2.2 percent for heart failure in the eight hospitals evaluated by Healthgrades. Minneapolis-St. Paul, ranked ninth, posted a range of 1.3 percent to 10.8 percent—an eightfold difference—for stroke at the 19 evaluated hospitals.   

Each city, a census-based statistical area, had to have at least four hospitals and at least one hospital that Healthgrades named a Distinguished Hospital for Clinical Excellence. That distinction is given to the top 5 percent of hospitals based on performance on 19 of 27 conditions and procedures. Overall, the national average mortality rate for these procedures is 6.52 percent.

The top 20 cities and their overall average mortality rates are:
1. Dayton, Ohio — 4.68 percent
2. Phoenix-Mesa-Glendale, Ariz. — 4.70 percent
3. Milwaukee-Waukesha-West Allis, Wis. — 4.84 percent
4. Cincinnati-Middletown, Ohio-Ky.-Ind. — 4.89 percent
5. Deltona-Daytona Beach-Ormond Beach, Fla. — 5.13 percent
6. Salt Lake City — 5.25 percent
7. Houston-Sugar Land-Baytown, Texas — 5.28 percent
8. Cleveland-Elyria-Mentor, Ohio — 5.28 percent
9. Minneapolis-St. Paul-Bloomington, Minn.-Wis. — 5.30 percent
10. Indianapolis-Carmel, Ind. — 5.33 percent
11. Detroit-Warren-Livonia, Mich. — 5.34 percent
12. Rochester, Minn. — 5.36 percent
13. Wichita, Kan. — 5.41 percent
14. McAllen-Edinburg-Mission, Texas — 5.43 percent
15. Lincoln, Neb. — 5.44 percent
16. Akron, Ohio — 5.44 percent
17. Denver-Aurora-Broomfield, Colo. — 5.45 percent
18. Chicago-Joliet-Naperville, Ill.-Ind.-Wis. — 5.45 percent
19. Allentown-Bethlehem-Easton, Pa.-N.J. — 5.47 percent
20. Brownsville-Harlingen, Texas — 5.51 percent